The complex, dynamic behavior of gas and steam turbines requires a flexible control system that provides state-of-the-art control, monitoring, and protection functions.
More specifically, in generator control, it is necessary to measure generator stator voltages and currents (typically sinusoidal signals) and subsequently use this information to calculate voltage magnitude, current magnitude, real power, frequency, and slip to synchronize the generator. It is well known that balanced poly-phase systems (such as 3-phase systems common to generators) with poly-phase instrumentation can transducer ac signals to dc without any inherent time delay or resulting ripple (ac components). Although in practice, some filtering is typically necessary. The same is not inherently possible for single phase instrument measurements. Although the generator is 3 phase, for economic reasons, only single phase instruments (such as a single potential transformer (PT) or a current transformer (CT)) or mixed transducering (such as a three phase PT and a single phase CT set) may actually be installed on the generator.
Thus there is a need for an apparatus and method capable of using single phase measurements or a combination of single phase and three phase measurements to form a poly phase signal set to calculate the voltage magnitude, current magnitude, frequency and slip using poly-phase instrumentation downstream (e.g., a calculation suite).